Balance the following equations under the solution condition

Balance the following equations under the solution conditions of acid or base as indicated. Please show work because im not even sure where to start!

a.) MnO4- (aq)+Br- (aq)=BrO3- (aq)+MnO2 (g) acid

b.)Br2(l)+IO3- (aq)= IO4-(aq)+Br-(aq) basic

Solution

a)

2MnO4(-) + Br(-) + 2H(+) -> 2MnO2 + BrO3(-) + H2O

b)6 H{+} + IO3{-}(aq) + 5 Br{-}(aq) = 2 Br2(l) + IBr(s) + 3 H2O